The use of automatic film processors is well established in the prior art. One such automatic film processor for example, is described and claimed in Copending application Ser. No. 630,634 filed July 13, 1984 in the name of the present inventor. As is well known in automatic film processors, the developer and other solutions are subject to change as film is developed. For example, in the course of the operation silver halide is reduced in the developer solution to metallic silver, whereby a reducing agent contained in the developer is consumed and a concentration of free halide in the developer solution occurs. For the continuous development of a series of film it is necessary to add to the developer a quantity of replenisher which corresponds to the actual consumption of the developer, to neutralize inhibiting by-products, and to drain away the used solution. In like manner, the various solutions used in the other tanks of the automatic film processor, such as the reversal tank, color developer tank, conditioner tank, bleach tank, and fixer tank must also be replenished from time-to-time.
Automatic equipment has been used in the past either to monitor and analyze the chemical constituents of the processing solutions, or to read the density of processed film strips, and to use the resulting data to control the replenishment of the various solutions in the film processor.
However, the prior art automatic equipment has proven to be unduly complex and expensive. The primary object of the present invention is to provide automatic equipment for replenishing the various solutions in an automatic film processsor without any need for the automatic equipment to analyze the processing solutions, or for the automatic equipment to read the density of processed film strips.
In accordance with the teaching of the present invention, the amount of concentrates consumed by various sizes of rolls of films, and various sizes of film sheets, on a square footage basis, is pre-calculated and stored in a computer memory. Then, prior to the processing of any particular film on any rack of the automatic film processor, data concerning the number and sizes of the rolls and/or sheets is fed into the computer, and the computer algorithm responds to the input data to cause appropriate control pumps to be turned on for computed times while the rack is placed successively in the tanks of the processor, so that the various solutions in the tank are replenished during the processing of the film, with amounts of replenishing solutions depending upon the total square footage of film on each rack.
Accordingly, the system of the present invention is simple and straightforward in that the automatic processing equipment itself does not monitor the various solutions in the tanks of the film actually being processed. Instead, and as described briefly above, a predetermined amount of replenishing solution is introduced into each tank of the automatic film processor as a rack of film is positioned in that tank, and the amount of replenishing solution introduced to each tank is determined by the square footage of film carried by that rack.
Briefly stated, in the system of the invention data is inputed to the computer designating the number and sizes of rolls or sheets of film next to be processed by the processor on each rack, and the computer is programmed to activate appropriate metering means so that the exact quantity of replenishment solution required in each tank of the processor for each rack of film to be processed may be supplied while the film is being processed.
The same computer may be used to control the automatic film processor itself, in the manner described in the Copending Application. The computer responds to the same input data fed into it for the replenishment control to provide appropriate controls for the film processsor itself.